The United Nations refugee agency reports deaths are spiking as refugees and migrants cross the Mediterranean Sea in record numbers in a desperate bid to reach European countries.

The U.N. refugee agency reports more than 300,000 refugees and migrants have made the perilous journey across the Mediterranean this year, trying to reach Europe. This is a huge increase over the 219,000 who made the crossing during the whole of 2014.

Meanwhile, some 2,500 refugees and migrants have died or gone missing.

UNHCR spokeswoman Melissa Fleming said this death toll does not include those who lost their lives Thursday when their boats capsized off the coast of Libya. She said the number of deaths in that incident is still unconfirmed.

“The survivors were taken to shore. We are hearing media reports that there are about 100 survivors," said Fleming. "Our office in Libya is checking with the coast guard and has not gotten the details yet. We believe 200 are still missing, feared dead.”

Fleming said another horrifying incident occurred Wednesday that highlights the methods used by smugglers, who cram people into unseaworthy vessels for profit.

She said rescuers who came to the aid of one boat off Libya found 51 people had died from suffocation in the hold. Survivors said the smugglers were charging money to passengers just to let them come out and breathe.

“One survivor, his name was Abdel, he is 25 years old from Sudan, told our colleagues, 'We did not want to go down there, but they beat us with sticks to force us. We had no air, so we were trying to get back up through the hatch and breathe through the cracks in the ceiling. But other passengers were scared that the boat would capsize so they pushed us back down and beat us too,'” Fleming related.

The cost of breathing is very high. Fleming said an orthopedic surgeon from Iraq said he paid 3,000 Euros to get his wife and young son on the top deck. She noted that most of the people confined to the hold were from sub-Saharan Africa and cannot pay that price.